The use of guidewires or core wires in conjunction with intravascular devices such as embolic protection filters or catheters is widely known. Typically, a flexible guidewire is inserted into a vascular lumen through a guide catheter, and then advanced to a desired location within the body. Once the guidewire is in place, an intravascular device such as an embolic filter can be advanced along the guidewire distal a lesion and deployed to prevent embolic debris from flowing downstream during, for example, an angioplasty or atherectomy procedure.
To facilitate steering and tracking through the tortuous vascular system, it is desirable to have a radially flexible guidewire capable of traversing the cavities of the body by applying a force on a proximal section of the guidewire. It is also desireable for the distal section of the guidewire to have a reduced profile capable of placement beyond a lesion or other protrusion in the vasculature with minimal interference. One such series of improvements has resulted in the use of a thin, flexible guidewire having a distally tapering cross-sectional area for improved steering, and a coiled wire helix disposed about an arcuate distal end of the guidewire for improved tracking.